Method of drying damp materials.



B. R. BESEMPBLDER. METHOD OF DRYING DAMP MATERIALS. APPLICATION FILED APR. 8, 1912.

nnuann nunonrnrnsnmrnnnnn, or enmorrnmztmo, GERMANY.

L mn'rnon or Danna mmr remnants.

To all whom, it may concern; V

4 Be it known that I, En'UAnn RUDOLPH Bnsnmzrnmnn, a subject of the German Emperor, and residing at Charlottenburg, Ger- 5 many, have invented certain new and useful Improvements in -Methods of Drying Damp Materials, of whichthe following is a specification. V

The hitherto knownv suggestions for quickly drying wood or other. materials that freshly hewn timber must be-quickly gotten ready for use, seasoned, the method of dryingit in a well Ventilated space always remained the most reliable and best, particularly when the wood Was intended for 25,the finer classes of work. It is, however, considered necessary that parquetry wood must dry in this manner for-years, and it is evident that a method which will achieve the same result within a couple of days, and so almost entirely avoid the enormous .costs, caused "by interest/on the purchase price of the lumber formany years, storage rent, wages, insurance prem1ums,and the like, will represent a great improvement in the art. y

Avery effective and rapid method of dry- .ing wood and other damp materials forms the subject matter of the present invention. This method consists in that the materials to bedried are exposed in suitable closed vessels, to a current of vapors of liquids,-

with the exception of water vapor. Materials'which. may be subjected to this rapid drying process besides wood, are for example, leather,- caoutchouc, india-rubber, amp textile goods, such as artificial silk,

d mp cellulose ornitrocellulose products, as

ell as wet photographic paper and the like.

I Vapors adapte will not mixywith water, such as benzene, benzol, naphthalene, ethylene-trich1orid carbon bisulfid, carbon tetrachlorid and j Specification 6: Letters mm.

- Application filed-April 8,1912. Serial No. 089,874.

. manner in which for use according to the present method are-,vapors of liquids which duced in the treatment of the wet materials Patented Apr. 22,1913.

can be. drawn in any desired manner from the drying vessels.

Hereinafter is given an example of the the method may be car, being had to the accomried out, reference panying drawing which illustrates a suitable apparatus for drying lumber, parts thereof being shown in section. For example, the fresh wood, f is placed'on a grate e, inaclosed jacketed rent of vapors of the kindabove set forth, say carbon-tetrachlorid, is sentthrough the vessel d, by means of a perforated pipe 0 located beneath the grate. These vapors are produced in a vessel a provided with a suitable vaporizing coil af and are led to the pipe 0 by means of a pipe I). The vessel d is connected by'means of .a pipe 9 to an eflicient condenser h in which the mixture of vapors and steam is condensed, and from which the product of the condensation flows vesseld. Then a curby means of a pipe i provided with a twoway cock is into a se arating vessel Z, for example a Florentine ask or thelike. Here the water, while at rest, is separated from the condensed drying medium according to their respective specific gravities, and the condensed drying medium may, if desired, flow of itself by gravity back to, the vessel a in which it is again converted into vapor. That portio'nof the drying medium which will have been condensed in the drying vessel (1 containing the material under treatment may also be conducted to the separator Zby a'suitable drain pipe 1'. The aqueous liquid collecting in the separator l and originally contained inthe treated material 1 overflows from the separator 1 into a collecting vessel 0 by pipe at for future treatment,

while the condensed drying medium passes through valved pipe m to. the vaporizing chamber a and is again vaporized and sent through the drying vessel at until the completion of the drying rocess y the fact that no re aqueous liquid is separated, and also'by the fact that the temperature in the drying vessel 0! begins to rise." The resinous and other substances which will be removed from the wood by thedrying medium will collect both. in the above-mentioned collecting vessel 0 and also in the vaporizing vessel a and may beremovedfrom the latter for further treatment after the drying medium has-been distilled 1s recognized oft. It.will, of course, be understood that the points of connection of pipes ,m-and n with the separator Z will depend upon the specific gravity of the vaporizing material used. If this material is lighter than water 7:. will be connected to Z near the bottom of the latter and will be provided with a suitable valve, While m will be connected to Z at a higher level. After'the drying process 1 has tained vapors of less high vacuum,

been completed that portion of the drying medium which may have been retained .in-the wood is driven out of the latter by sending steam of a suitable temperature into the jacket of the vessel (1 and, if necessary, while the vessel is under a more or or air or inert gas may be sent through the the substance used, and the medium is then recovered in a Well known manner. The steam or inert gas is admitted through the pipe 00. By this method, which can be carried out. with a simple plant, the wood will be dried within a comparatively short time. without losing its valuable properties. Besides, valuable substances coming from the dried materials, such as resins and others which were hitherto lost, may be recovered from the aqueous liquid in the collecting vessel 0 and from the residues in the vaporizer a.

The'above-described method may be employed in all. cases in which any damp ma terials have 'to be dried in a rapid and careful manner, It avoids the danger of oxidation experienced in the air-drying method,

and in cases where the value of the liquid employed for producing the vapor currents to bedried, it may, under certain circumstances, be of advantage to carry out the treatment with the drying medium, (the vapors) in such a manner that the drying processis commenced with a liqui d of a low boiling point, and continued with a liquid of a higher boiling point, or vice versa. Furthermore, it may, in drying certain materials, be advisable, with regard to the sub- 1 stances to be removed therefrom, to commence the drying process with a vapor of the aforementioned kind, and to continue it with the addition of the vapor of aliquid having a lower boiling point, or to substitute another kind of drying vapor for the vessel to displaeetherefirst drying vapor employed, and so on.

Lastly, mixtures of diflferent vapors may be employed. For example the-vapor from a mixture of benzene and benzol may be introduced into the drying chamber and then if necessary the vapor from a mixture of ethylene-trichlorid and carbon-bisulfid. It

is of course obvious that in some instances the vapors of mixed liquids W111 produce a.

quicker and better drying of the substances to be dried than the vapors of a single liquid and their use is determined by the character of the substance to be dried and the nature of the material to be removed from the sub stances to be dried.

In practising my 'nvention it has been 'found that different vapors or mixtures of vapors may be used to advantage for drying'difierentjspecies of wood, and also for drying young and old wood of the same species, Consequently theparticular vapor adapted for dryin in the best manner any particular kind 0 wood should be determined b experiment, the age of the wood (determlned by the diameter of the tree) being always borne in mind.

I claim- 1. A method of drying materials, which I comprises exposing the material to the vapor of a liquid other thanfwater and not miscible therewith, and thereafter exposing the material to the vapor of another liquid of the same character but of a different boiling point.

2. A method of drying materials, which comprises exposing the material to the vapor of a liquid other than water and not miscible therewith, and thereafter exposing the material to the vapor of another liquid of the same character but of a lower boiling oint.

3. A method of drying materials, which comprises exposing the material in a closed chamber to a current of vapor of a liquid other than water, and thereafter exposing the material in a closed chamber to a current of vapor of another liquid of the same character at atmospheric pressure, and conducting from said material the resulting-vapor mixtures.

4. A method of drying materials, which comprises subjecting the material in a closed chamber to a current of vapor of a liquid other than water and non-miscible therewith, then toa current of vapor of another liquid of the same character at atmospheric pressure, and conducting from said material the resulting vapor mixture. g

5. A method of drying materials, which comprises exposingthe said materials successively to a current of the vapors of several liquids other than water and not miscible therewith.

6; A method of drying material, which of vapor of a liquid other than water, and then to a current of vapor of another liquid of like character but lower boiling point and at atmospheric pressure, and conducting the resulting vapor mixtures from the material.

7. A method of drying material, which comprises subjecting the material at atmospheric pressure first to a current of vapor of a liquid other than water and non-miscible therewith, and then tothe vapor of a liquid of similar character but lower boiling point, and conducting the resulting vapor mixtures from the material.-

8. A method of drying materials, which comprises subjectin the material successively to currents o vapor of difierent liquids other than water, and conducting the resulting vapor mixture from the material, j 9. A method of drying materials, which comprises subjecting the material at atmospheric pressure to successive currents of vapors of different liquids other than water and non-miscible therewith, and conducting the resulting vapor mixtures from the material.

10. A method of drying materials, which comprises subjecting the material at atmospheric pressure to successive currents of vapors of difi'erent liquids other than water and of different boiling points, and con-' ducting the resulting vapor mixtures from the material. i

11. A method of drying materials, which comprises subjecting the material at atmos pheric ressure to successive currents of vapors oi difierent liquids other than water and non-miscible therewith, and of different boiling points, and conducting the resulting vapor mixtures from the material.

12. A method of drying materials, which comprises subjecting t e material at atmospheric pressure to the action of a current of vapor of mixed liquids other than water and conducting the resulting vapor mixture from the material.

13. A method of drying materials, which comprises subjecting the material at atmospheric temperature to the action of a current of vapor of mixed liquids other than water and non-miscible therewith, and conducting the resulting vapor mixture from the material. I

In testimony whereof I afl'ix my signature in presence of two witnesses.

EDUARD RUDOLPH BESEMFELDER; 

